I was extremely excited when I saw this concept for the first time. Scan or enter all your credit cards and loyalty cards into one device that's the size of a single credit card. with encryption, NFC, and a touch screen e-ink display...this may truly be the only card that you ever need to carry. I'm a little concerned about the overall security and hackabiluty of this card device as opposed to using an epay option on your cell phone, as you would actually have to let someone take this card with them for payment. Thoughts? Would any of you use this device?